Sectionalized aerial duct



Oct. 12, 1948.

(5. VAN ANTWERP SECTIOHALIZED AERIAL wow 2 Sheets-Sheet 1 Filed Jumps, 1945 INVENTOR. GEORGE $.VANANTWERP v AT ORNEY 0d. 1948- v G. s. VAN ANTWERP 2,451,004

SECTIONALIZED AERIAL pucw Filed June 23, 1945 2 Sheets-Sheet 2 IN VEN TOR.

'GEORGE S. VANANTWERP ATTORNEY Patented Oct. 12, 1948 U NlT-ED STATES" i AT- EN -l" se-r ems 3EGTI0MALIZEDAERIALYDUCT gGeorgeJ-S. 'Van Antwerp, Norristown, Pa.

Apiilica'tionfiund 23, 1945, Serial'N0. 601,258

A'Claims.

.llnlsin sulated electric power or communication cabieswhosemechanical"characteristicshareesuch Eithat they' are elnot": self-supporting, when z'c'arried iiaeria'lly,"are :usually suspended alongthe spans of "messenger cables by suitably spa'eedzrings lin'l:-

ing ithem to thermessengers. The suspended -acables, which are .zusual'ly :heavy :and sheathed #W ith lead; havev an extremely "short life due. 'to.the abra'ding action or 'itherrings i-andi' the vibration incident to 'SUChlCOI'lStillCtl'On. xDespitealloying of the Iead sheath "with :anti-monyor other-:ele- "ments -'to improve endurance, and the use of various types c'if'ringisa'ddles' to distribute stresses, the life-of this type of cable is nineatisfactory.

Also, cables exposed 'in such'zmanner rare ex-2 trem'ely susceptible to damage from shot or small caliber rifle fire aimed at birds sitting on the "messengers. They are 'ralsos-ubjeet to abrasion -by tree limbs and to' damagefromaccidentetlfires 'in their immediate proxirnity. Furthermore, the :1

*Weight is transmitted by the rings t0= points of local stress concentration on the messenger cable, causing undue Wear aridcorrosionat such points.

The objects of my invention 'are: to provide a sectionalized aerial ductsystem in whichscables,

"hosesffiexible tubes, or-the -1ike, are-supported substantially conti-nuous'ly -a'long their entire "lengths; to produce "a -sectionalized -aerial duct system providing a substantially complete -en "closure"shielded-from =-diret=solar radiation and flames 'from accidental fires; to *provide --a sectionalized (aerial duct system providing an armored encl'osure to =provide'sectionalized 'aerial "d'uct'um'ts adapted to beremovably attached-to anaerial messenger; to provide a messenger supported;"sectionalized=aerial' duct system for cables, or the like;in=which'the duct sections can be installed or'removed 'with the cable in "place; with utmost ease and'simplic'ity; .and to "produce an integrated, .sectionalized aerial duct system having rassociatedmaccessory units for terminations, messenger-supports, taps; bifurcations, .etc.

"With-fihGSB"&fid other objectsdn viewwhich will appear from -.the;ensu1 ng-=description :and ;claims, 'thewfollowing describes: the details of-conist-ruetion'and' combination of, partsof a specific 'rembodimentof my invention, which I illustrate as-Jan --;exam-p1e, and which will 7 best be understood -whenread in conjunction with the-accompanying drawings, in which: "Eig. 'lnis aaz perspective viewwshowing" the separate'tparltsof ea standandzsectionof zaeriai duct; Fig. :2 -is tzan end elevational view ao'f an Eas semblect standard ductfsection;

- ofisetsaddIe-amember;

Fig. *4 vis: a fragmentary "perspective --view-of-1a section of fiexib'le'conduit Fig. Sris airagmentary perspective viewzshow- :ingva :l-messengerwcarrying zaducti run including an oifset section;

"Fig. 6 is aatransverse sectional viewaof aisaddle "memberassembled? to a flatcoverz 2mernber;

Fig. '7 is aside eleva't-ionalrviewishowingxeonstruction at support for a straight run of -telnet;

:Fig. 8sis: aside view set the mountings-bracket shown in'Figq'l Fig. Qrisaperspeetive view illustratingtmetho'd 10; construction at"terminals and bends;

Fig. 10 .is "a1fragmentary-sectional' vieweof saddle member :showingumethod. :of ifiaring ':ends and drainage apertures; Land ""11: isza perspective view ofrlatmodi fication of "myiin'ventioni for 'use. in ".place:rofrxnessenger rings.

Referring to rthe drawings, 11 'have. sh'own in Fig-.1 a messenger cable? Zhumwhioh'is mduntei'd a hanger cover memberKZI formedi'or bent from sheet material lintthe shape of an inverted "U- f old at the top constituting a longitudinal central groove :22, :thence slopingl downwardly one-either side to vertical sides :23 andl' finally ieldedover inwardly and upwardly to form grooves or -fol-ds :24. A co-operatingz saddle -mem-ber 25- -o'f relatively thin "material'is fashioned in a "U '-shape with 'itsedges foldedover outwardly-and :downwar'dly-to form grooves-or folds zfi whiohaelasp or interlock-with the'groov-es 24- of the hanger 2! as shown in- FigTZ.

The member I and 25 thus form-a continuous ductway of box shaped cross section, *of which the hanger 'meniber' Z I- defines the ceil-ingand the saddle member 25 defines thefioor; f Or -accommodating one or morecables.

'The members' 'll and" 25-may -be -unitedby-=s1id- 'ing in from theends'or bysqueezingorcompressingthe sides ofthe saddle 25 together, "raising thesadd1e within the hanger 2| until the -grooves 26 are above the'gr-oove 'M, releasing the-compression on the sides of the saddle, permitting itito spring back'to its :initial:shap'e,sandfallowin'g the saddle J to .:drop into: the: position illustrated in Fig. :2. Assembly of themembers may also be accomplishednzbyi springing :apartf thesidesdi! of 1 the ::hanger :tinstead :of :squeezing iithe lzsaid'dle. ,The hanger?! and saddle :25 are readily seep- .arated 'by vthe xreverselof ieither'iof these sprocedures. Parallellongitudinal slits 21.: arecutin :the :saddle 5v :inwardiyv from :the :ends to form locking fingers 28 just below the grooves 28. When bent outwardly as shown in Fig. 2, with a screw driver or other simple tool, the fingers 28 lock the members 2| and 25 together to prevent separation either by lifting or sliding.

On installing my duct system, I prefer to stagger the relative positioning of the hanger and saddle members as shown in Figs. 5, 7 and 9, although they may be coextensive is desired. It is also to be understood that they may be of any suitable length, and a particular hanger need not be the same length a the associated saddle.

When it is desired to have additional cables enter the duct run at any point, to be supported along with cables already in place or to be spliced thereto, a vertical-offset saddle 30 is used. The offset 30 is identical with the saddle 25 except that it is tapered longitudinally, with the shallower end 3| matching the ends of the saddle 25. The offset 30 i of uniform width, the deeper end 32 being of depth suitable to admit the branch cable 33 below an adjacent saddle 25', as illustrated in Fig. 5, and to enclose the splice if the cables are joined. Protection for the branch cable 33 is provided by means of a section 34 of flexible conduit of the interlocking helix type well known in the art. The offset 30 is also used at terminations where the cable leaves the duct run in a downwardly direction, as shown in Fig. 9.

In the construction at the messenger support for a straight run of duct, the hangers 2| are installed with the messenger 2U exposed for a short distance either side of the messenger clamp 35, as shown in Fig. '7. The saddles 50 are contiguous beneath the clamp and are supported for part of their lengths by the hangers 2|. Over the portion of the saddles 50 not topped by the hangers 2|, there is fitted a flat cover member 40. The fiat cover 40, illustrated in Fig. 6, is similar to the hanger 2|, differing only in that the groove 22 and sloping sides are replaced by a flat, horizontal portion 4|. The saddle 2-5 and offset 30 are attached to the flat cover 40 in the same manner as to the hanger 2|. As shown in Fig. '7, the flat cover 40 may be readily bent to conform to the small angle between the saddles 50.

At cable terminals, the cable is carried from the end duct to the desired destination within a length of the flexible conduit 34, as illustrated in Fig. 9, it being understood that the messenger itself may be continued beyond the end of the duct system to a suitable supporting structure. The construction at bends in the duct run is similar to the construction at terminals, the cable being carried from the end duct 5| of one span to the end duct 52 of the angularly disposed span within a length of the flexible conduit 34.

The edges of the ends of the saddles 25 and 32 are preferably flared outwardly, as illustrated by the flare 6|] in Fig. 10, for the purpose of minimizing chafing of the cables or other units carried, in the event they are to be pulled through the ducts. The flare 60 also provides a drip edge to prevent accumulation of rain water. In case additional relief of rain water is needed, the saddles may be perforated at the botom, as shown by the aperture 6!, spaced as desired.

With slight modification of the locking means described in the foregoing, and when out down to suitable lengths, my hanger and saddle duct members may be used as rings which will minimize scoring and chafing of the mess g s caused by the rings in present use. In Fig. 11, I show a ring assembly 10 comprising a hanger member ll which is a fore-shortened replica of the hanger 2|, attached centrally to a co-operating saddle member 12 which is identical to the saddle 25 in cross-section and somewhat longer in length than the hanger H. At each end, the hanger TI is provided with a locking finger 13, formed by cutting parallel, longitudinal slits in the sides 23', the two finger being diagonally opposite. The fingers T3 are bent inwardly over the folds 26 to prevent vertical separation of the members. To prevent longitudinal sliding separation of the members H and "I2, a vertical cut; 14 is made in the outer part of the fold 26' near each end of the saddle 12 on the same side as the adjacent finger 13. outwardly of the cut 14, the outer, downwardly projecting part 15 of the fold 26' is pinched inwardly to form a lock. The diagonally opposite pairs of fingers 13 and pinched parts 15 or the ring assembly 10 effectively prevent separation of the members H and 12. When it is desired to separate these members, however, the fingers T3 are readily straightened with ordinary pliers, permitting the saddle to be removed by lifting, squeezing and lowering it out of engagement with the hanger H. The end edges of the groove 22 and the saddle 12 may be flared, similar to the flare 60, or rounded to minimize chafing of the messenger and the cables being supported. The groove 22 i pinched or otherwise suitably narrowed to engage the messenger tightly enough to prevent slipping under ordinary service conditions.

From the foregoing, it is evident that the cable may be drawn into ducts already in place or that my duct sections may be installed about a cable disposed aerially in proper relation to the messenger including existing messenger-supported cable. In the latter case, the hanger i fitted over the messenger and the saddle slid or snapped into place, any interfering rings or other supporting structures being removed as installation proceeds. Removal of individual duct sections for replacement of duct members or for work on the cables carried therein is readily accomplished by the previously described procedure for releasing the saddle member from the hanger member.

Although I have described and shown my duct system as used to carry cables, it is obvious that it may be used with equal effectiveness for supporting aerial runs of hose or other flexible tubing for the transport of fluid or pulverized materials.

Also, it is to be understood that the duct members can be made of any materials having the desired mechanical properties, such as metals or plastics, nor is it necessary that the interlocking parts be of the same material. For example, the hangers may be Of resilient material and the saddles of non-resilient material, in which case the members may be engaged by sliding them together or by springing open the hangers as previously described. Again, both members may be formed of a rigid material, such as glass or fiber, and installed by sliding them into engagement. Ducts of glass or other good dielectric may be of advantage in certain locations to give electric cables additional impulse strength.

When it is desired to armor the supported lines, the ducts may be made from suitable thickness of high strength material. If support of weight only is required, they may be constructed from very thin or light materials, or from woven or perforated materials such as expanded metal, since the weight distribution is uniform on the duct members as well as the messenger.

Enclosure of electric power services in my ducts has the added advantage of providing substantial anti-tampering protection.

I claim:

1. A messenger-supported aerial duct system composed of a plurality of contiguous sections of duct, each section comprising a hanger member and a saddle member the hanger member having a groove for receiving the messenger and having downwardly and outwardly diverging portions, and the saddle member having upwardly and outwardly diverging portions interlocked with the downwardly diverging portions of the hanger member and forming therewith a continuous ductway for one or more cables, of which the hanger member defines the ceiling and the saddle member defines the floor.

2. A messenger-supported aerial duct system composed of a plurality of contiguous sections of duct, each section comprising a hanger member and a saddle member, the hanger member having a groove for receiving the messenger and having downwardly and outwardly diverging portions, and the saddle member having upwardly and outwardly diverging portions interlocked with the downwardly diverging portions of the hanger member and forming therewith a continuous ductway for a plurality of cables, of which the hanger member defines the ceiling and the saddle member defines the floor, one of said duct sections having a saddle member longitudinally tapered and having a shallow end conforming to the normal cross section of the ductway and a deep end extending beneath the bottom of an adjacent saddle member, a cable extending through all of the section of said ductway, and a second cable entering the ductway through said tapered saddle member.

3. In combination with an aerial messenger, a support for a cable to be suspended therefrom '6 comprising a hanger member depending from said messenger, and a saddle member depending from the hanger member, said hanger member and saddle member being provided with folded edges whereby they are slidably interlocked, one of said members being litted to provide a finger at its folded edge, and said finger being bent to engage the other of said members and thereby EreVent vertical separation between said memers.

4. In combination with an aerially supported messenger, a duct system comprising a plurality of contiguous duct sections each comprising a hanger member and a saddle member, aid members being separably attached to form a unitary structure defining a ductway generally paralleling said mesenger, the hanger members depending from the messenger and the saddle members depending from the hanger members, the hanger members being positioned in staggered relation to said saddle members, a support for the messenger intermediate of said duct system, the hanger members to either side of said support being spaced therefrom and the saddle members being continuously abutted past said support, and a cover member equal in length to the spacing between the hanger members to either side of said support, said cover member engaging the saddle members in the space between the hanger members at said support.

.GEORGE S. VAN ANTWERP.

REFERENCES CITED Thefollowing references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 324,225 Carhart Aug. 11, 1885 526,663 Abrahams Sept. 25, 1894 989,212 Van Nostran Apr. 11, 1911 1,967,134 Short July 17, 1934 

